Microstructures and properties of CoCrCuFeNiMox high-entropy alloys fabricated by mechanical alloying and spark plasma sintering

ABSTRACT CoCrCuFeNiMox (x values in molar ratio, x = 0, 0.2, 0.4 and 0.8) high-entropy alloys were prepared by mechanical alloying and spark plasma sintering method. The effects of Mo addition on microstructure and mechanical properties were investigated. The X-ray diffraction (XRD) result showed that the addition of Mo into CoCrCuFeNi high-entropy alloy (HEA) changed the original phase constitution from FCC to FCC + σ + μ and the peak intensity of (1 1 1) shifted to the left and decreased steadily. The field emission scanning electron microscope confirmed that the Cu-rich second FCC phase disappeared and the σ phase with a tetragonal structure expanded as the Mo content was increased. Additionally, a high density of dimple-like features were seen in CoCrCuFeNi HEA while typical quasi-cleavage facets could be observed from the fracture surfaces of the HEAs with the addition of Mo. The Mo0.8 alloy showed a good wear resistant and appropriate strength with fracture strain 22.70%, fraction coefficient 0.65, hardness 530 HV and compressive strength 1448 MPa. Special theme block on high entropy alloys, guest edited by Paula Alvaredo Olmos, Universidad Carlos III de Madrid, Spain, and Sheng Guo, Chalmers University, Gothenburg, Sweden.

[1]  Hidemi Kato,et al.  Structure and properties of ultrafine-grained CoCrFeMnNi high-entropy alloys produced by mechanical alloying and spark plasma sintering , 2017 .

[2]  T. Shun,et al.  Microstructure and mechanical properties of multiprincipal component CoCrFeNiMox alloys , 2012 .

[3]  T. Shun,et al.  Age-hardening of the CoCrFeNiMo0.85 high-entropy alloy , 2013 .

[4]  P. Rivera-Díaz-del-Castillo,et al.  Modelling solid solution hardening in high entropy alloys , 2015 .

[5]  Y. Hsu,et al.  Corrosion behavior of FeCoNiCrCux high-entropy alloys in 3.5% sodium chloride solution , 2005 .

[6]  Akira Takeuchi,et al.  Calculations of mixing enthalpy and mismatch entropy for ternary amorphous alloys : Special issue on bulk amorphous, nano-crystalline and nano-quasicrystalline alloys , 2000 .

[7]  P. Liaw,et al.  The high-entropy alloys with high hardness and soft magnetic property prepared by mechanical alloying and high-pressure sintering , 2016 .

[8]  Jian Lu,et al.  High-entropy alloy: challenges and prospects , 2016 .

[9]  A. Takeuchi,et al.  Calculations of amorphous-forming composition range for ternary alloy systems and analyses of stabilization of amorphous phase and amorphous-forming ability , 2001 .

[10]  Bin Liu,et al.  Deformation mechanisms of Mo alloyed FeCoCrNi high entropy alloy: In situ neutron diffraction , 2017 .

[11]  Ł. Rogal Semi-solid processing of the CoCrCuFeNi high entropy alloy , 2017 .

[12]  Yong Zhang,et al.  Effect of Nb addition on the microstructure and properties of AlCoCrFeNi high-entropy alloy , 2012 .

[13]  Vinod Kumar,et al.  Structural evolution of spark plasma sintered AlFeCuCrMgx (x = 0, 0.5, 1, 1.7) high entropy alloys , 2016 .

[14]  Jincheng Wang,et al.  The phase stability of Ni2CrFeMox multi-principal-component alloys with medium configurational entropy , 2015 .

[15]  J. Yeh,et al.  Deformation and annealing behaviors of high-entropy alloy Al0.5CoCrCuFeNi , 2009 .

[16]  Nikita Stepanov,et al.  Effect of V content on microstructure and mechanical properties of the CoCrFeMnNiVx high entropy alloys , 2015 .

[17]  D. Miracle,et al.  A critical review of high entropy alloys and related concepts , 2016 .

[18]  Jun Wang,et al.  Enhanced mechanical properties of a CoCrFeNi high entropy alloy by supercooling method , 2016 .

[19]  Huizeng Li,et al.  Microstructures and compressive properties of multicomponent AlCoCrCuFeNiMox alloys , 2010 .

[20]  Z. Cai,et al.  Effect of Ti content on the microstructure and mechanical behavior of (Fe36Ni18Mn33Al13)100−xTix high entropy alloys , 2016 .

[21]  Sheng Guo,et al.  Phase selection rules for cast high entropy alloys: an overview , 2015 .

[22]  Bin Liu,et al.  Ductile CoCrFeNiMox high entropy alloys strengthened by hard intermetallic phases , 2016 .

[23]  Anding Wang,et al.  A ductile high entropy alloy with attractive magnetic properties , 2017 .

[24]  B. Murty,et al.  Phase Evolution and Densification Behavior of Nanocrystalline Multicomponent High Entropy Alloys During Spark Plasma Sintering , 2013 .

[25]  Govind,et al.  Processing and Consolidation of Nanocrystalline Cu-Zn-Ti-Fe-Cr High-Entropy Alloys via Mechanical Alloying , 2013, Metallurgical and Materials Transactions A.

[26]  C. Woodward,et al.  Accelerated exploration of multi-principal element alloys with solid solution phases , 2015, Nature Communications.

[27]  Zushu Hu,et al.  Microstructures and compressive properties of multicomponent AlCoCrFeNiMox alloys , 2010 .

[28]  Z. Kováčová,et al.  Microstructure and mechanical properties of Ni1,5Co1,5CrFeTi0,5 high entropy alloy fabricated by mechanical alloying and spark plasma sintering , 2017 .

[29]  T. Shun,et al.  Nanostructured High‐Entropy Alloys with Multiple Principal Elements: Novel Alloy Design Concepts and Outcomes , 2004 .

[30]  B. Klöden,et al.  High-entropy alloy CoCrFeMnNi produced by powder metallurgy , 2017 .

[31]  N. Jones,et al.  High-entropy alloys: a critical assessment of their founding principles and future prospects , 2016 .

[32]  S. B. Luo,et al.  Liquid phase separation and rapid dendritic growth of high-entropy CoCrCuFeNi alloy , 2016 .